It is well known to provide blades of an upwind wind turbine with supporting means on the windward side of the rotor plane extending from the blades to for instance an extension of the main shaft. Such a configuration is e.g. shown in U.S. Pat. No. 4,403,916 and WO 86/02701. The object of such configurations is to support the blades against the forces of wind by exerting a tensile force in the direction against the wind.
U.S. Pat. No. 4,403,916 discloses a wind turbine with a generally vertical support tower, and a generally horizontal drive shaft, which is connected to a vertical drive shaft. The blades of the wind turbine are reinforced by wire cables to strengthen the blades against gravitational pull and to hold the blades against wind forces. The wind turbine further comprises a tail section or a vane that continuously yaw the horizontal drive shaft to point into the wind.
U.S. Pat. No. 5,354,175 describes an upwind configured wind turbine comprising a teeter hub. The teeter hub comprises a yoke assembly on the rearward side of the blade and two damping teeter control mechanisms for preventing teetering of the hub.
GB-A-1 592 114 describes a downwind configured wind turbine, where wind turbine blades are supported by struts on a windward side of the wind turbine blade.
U.S. Pat. No. 4,316,699 also describes a downwind configured wind turbine, where wind turbine blades are supported by struts on a windward side of the wind turbine blade.
U.S. Pat. No. 4,183,715 describes a windmill having vanes supported by rigid struts, which are connected to pivotal joints.